The overall aim of my research program is to determine how hormones regulate reproduction and behavior. As a model for understanding this regulation, I am using the lobster, Homarus americanus. Lobsters and other decapod crustaceans produce methyl farnesoate (MF), a sesquiterpene that is related to insect juvenile hormone. Because of structural similarity to JH, MF is suspected to have roles similar to JH, which regulate insect metamorphosis, growth, reproduction and behavior. However, the unequivocal demonstration of a role for MH has proven difficult, largely because it is difficult to manipulate endogenous levels of MF. The synthetic site of MF is the mandibular organ (MO) which is regulated in part by neuroendocrine compounds from the eyestalk. One of these is a peptide that inhibits MO function (MOIH, MO inhibiting hormone). The isolation and eventual synthesis or expression of MOIH would provide a convenient tools for controlling MF levels in vivo in studies of its physiological roles. During the research period I plan to pursue three specific goals that are fundamental to this overall research objective: 1) The characterization and sequencing of MOIH. 2) The use of synthetic MOIH or MOIH purified from lobsters to produce an anti-MOIH antiserum. 3) The use of this antiserum to establish parameters for regulating MF levels in vivo.